Rudder-operating mechanism for aircraft



Dec.'11, 1928. 1,694,496

' T. P. WRIGHT ET AL RUDDER OPERATING MECHANISM FOR AIRCRAFT Filed July 13, 1926 git is /1 i zi 4 IN VEN TORS W1 LLIAM WAlT JR- THEODORE P. WRIGHT &

- 30 and greater as the rudder is swun' 40 the pilot of Patented Dec. 11. 192.8

U iED STA THEODORE r. WRIGHT, or roRT WASHINGTON, AND WILLIAM WAIT, 3a., oreanmzn CITY, NEW YORK, ASSIGNORS TO CURTISS PORATION on NEW YORK.

AEROI'LANE dbMOTOR 60., INQ, ACOR- RUBBER-OPERATING MECHANISM FOR AIRCRAFT.

Application filed July 13,

Our invention relates to control surface operating mechanism for aircraft and is concerned more particularly with an auxiliary control operating in conjunction with an ordinary control to exert on the rudder or other control surface of'the aircraft a constantly increasing operating force tending to continue its movement in either direction immediately such movement is initiated by the ordinary control.

In a twin-motored aeroplane for instance, it is not an uncommon occurrence to operate the machine on a single motor. When this is done, and regardless of which motor (right or left) is in operation, a turning couple is set up with the result that the machine turns either to'the right or left as the case may be. To counteract this turning couple it is the ordinary practice to swing and hold the rud-- der either to the right or leftthruthe operation of the ordinary rudder control. Where such operation of the rudder continuesfor a period of long duration, the constant and prolonged pressure by the pilot on the rudder control becomes very fatiguing. Moreover, in the operation of the rudder or ruddersof the larger types quired to be exerted on the rudder control device becomes gradually increasinglygreater fromits 3 neutral or unefli'ective position. uch pressure increase is due primarily to the fact thatv in' biasing the rudder the air pressure onone side or. face thereof (that 'face toward the di- 3'5 rection of movement)becomes-greater and still greater as the rudder continues tomove."

The primary object of the present invention is to provide an auxiliary ruddercon-. trol mechanism which is adaptedto relieve the fatigue of holding the rudder position should necessity therefor in a biased wh1ch,.at the same time is so orarise', and

ganized and constructed as to exert'on the rudder a constantly increasing operating ,force tendingto continue its movement in either direction immediately f'such movement 7 is initiated bythe ordinary rudder-control.

A further obj ect'of the invention is; the pro-:. vision of simple means for regulating the 5 1 magnitude of the operatingrforc'eadapted to be exerted on said ordinary. rudder control,

A still further object of the invention is to rovide an auxiliary rudder control device which can he used on or in connection of aircraft, the pressure rethe fuselage with 1926. Serial No. 122,144.

suchordinary rudder control mechanism as is now in general use.

Other objects and vention will be hereinafter set forth:

In the drawings, wherein like reference characters denote like or corresponding parts,

Fig. 1 is a side elevation of a portion of an aeroplane having installed thereon the auxiliary operating rudder mechanism of our invention;

Fig. 2 is a side elevation of such auxiliary mechanism showing its relation to the ordinary rudder control;

/ Fig. '3 is a-fragmentary-view in which the adjusting arm and its associated adjusting pin are shown, and

advantages of the in-' res "PATENT OFFICE.

Fig. 4 is a diagrammatic illustration of the y complete rudder operating mechanism. 7

In the embodiment of the invention selected for illustration, only that'portion of an aeroplane fuselage 10 in the vicinity of the pilots cockpit ll-is shown. Suchaeroplane, in additionto the fuselage 10 and cockpit 11 comprises the supporting surfaces 1212 and landing gear 13. Within the cockpit 11, and also withm convenient reach of the pilot when seated therein, we provide a now common type of rudder control mechanism 14. Such mechanism includes two separate foot control devices 1515 mountedupon a common axis of. rotation extended transversely of the fuselage 10 and each provided with a stirrup 16 against which adapted to hear. The control devices 15 (see I Fig. 4 are interconnected as at l7 by a flexible ca le carried over pulleys 18-1 8 positioned in advanc. of said device and one at either side of the machine. From said dethe feet .of the pilot are f vices 15 other and further cables 1919 are carried rearwardly, either within or without for connection with the rudder control surfaceQO (there may be more than one such surface), usually positioned, at the extreme rear end of the machine. By exerting foot pressure on either said device 15- 15 therud'der 2Q isbiased either to the right or left as the case may be.

Shafts 21.journal'ed in suitable bearings (not shown) support said rudder control.devices1515 in the manner shown.

As previouslyfexpla ned and particularly in a twin-motored aeroplane where it becomes erateflthe. machine ona single motor, 'consi erable muscular effort is .re=

necessary .to 0' in which there is a tendency to turn. To rel1e've the pilot of this muscular fatigue and at the same time to aid in the ordinary operation of the rudder control, the auxiliary rudder control mechanism is provided. Preferably such mechanism consists'of an adjusting lever 22 pivoted as at 23 and having associated with it suitable pawl and ratchet mechanism 24.

Said lever 22 is preferably located at one side of the pilotsseat within the cockpit of the machine. At its lower end said lever 22 has fastened to it as at 25 a flexible connection 26 which, at its opposite end-is similarly fas tened as at 27 to the outer end of an adjusting arm 28 mounted on the shaft 21 of the ordinary control. 'Inte'rmediately of its ends said connection 26 has interpolated therein a yielding member 29 which is adapted to maintain said connection, at all times, under more the axis of said s aft.

or less tension. The adjusting arm 28, as stated, is mounted on one or the other of the shafts 21. Preferably such arm 28 extends off from said shaft at an acute angle to the rud der control device with which or adjacent to which it is mounted. By extending said arm off from said shaft 21 in the manner indicated, and by carrying the connection 26 at tached to its free end ofl' therefrom toward one side of its axis of rotation and to a point in the plane of and at one side of said axis,

such connection will exert at all times on said arm an operating force tending to actuate the ordinary control in one or the other direction, depending upon which side of said ordinary control said arm is disposed at the time. The

arm it will be noted, may be shifted (see Fig.'

2) from one to the other side of the shaft 21 that the force exerted thereon thru the action of the connection 26 may be applied toward moving the control device 14 in either direction. For this reason the idler 30 over. which said connection 36is carried is so positioned as to bring one ed e thereof in the plane of Stops 31-31 positroned, one at either side of the control device 14 limit the movement of the adjusting arm.

Ar auxiliary control device characterized as above set forth exerts on the rudder control device a constant pull tending to increasingly swing said device in that direction toward which its movement is initiated. This radually increasing force or pull is obtained rom the yielding connection 29 and the relationship'of the idler 31 to the adjusting arm 28 and from the position of said adjustin arm relatively to the control device 14 wit which it is associated. By manipulating the adjusting lever 22 the magnitude or degree of force exerted on said control device may be regulated. Thru the interconnection 17 between the control devices 1414 the pull exerted on one is transmitted quickly and simultaneously to the other, and by way of the connections l9-19 is further transmitted to the rudder control surface 20at the tail end of the machine. A pin 32 provided at the outer or free end of the adjusting arm 28 and'extending inwardly as shown in Fig. 3, enables the pilot, with the aid of his foot, to shift said arm 28 from one to the-other positions of adjustment indicated by the full lines and dotted lines, respectively, of Fig. 2.

While wehave described our invention in detail in its present preferred embodiment, it will be obvious to those skilled in the art after understanding n invention, that various changes and modi cations may be made therein without departing from the spirit. or scope thereof. We aim in the appended claims to cover all such modifications and changes.

What we claim is: b e 1. In control surfaceoperati ng mechanism for aircraft, a pivotally mounted control device, a connection betwee'n said control device and said control surface, an arm extend ed off from the pivot axis of said control device to define therewith an acute angle, an adjusting device, and a yielding connection between said. adjusting device and said arm for increasingly exerting on said control surface a force tending to aid its movement in a given direction immediately such movement is initiated. I

2. In control surface operating mechanism for aircraft, a pivotally mounted control device, a connection between said control device and said control surface, a guide mounted at one side of the pivot axis of said control device, and means fastened at one end to said control device and carried from said point of fastening over said guide to increasingly exert on said control surface a force tending to aid its movement in a given direction, and a tension means associated with said last mentioned means.

' 3: In control surface operating mechanism for aircraft, a control device having a fixed pivot axis, an arm exending off from said pivot axis and shiftable from one to the other side of said control device to define therewith in either position of adjustment an acute angle, stops carried by said control device, one at each side thereof, and against one or the other of which said arm is adapted to bear, and means fastened to said arm and extended off therefrom in the general direction of its axis of movement for increasingly exerting on said control surface a force tending to aid its movement in a given direction, and regardless of said arm adjustment, saidlast mentioned means having incorporated therein'a tension device.

4. In control surface operating mechanism .for aircraft, a'control device having a fixed pivot axis, an arm extending off from said pivot axis at an acute angle to said control device, a guide mounted at one side of said pivot axis, a connection between said control device and said control surface, and means extending off from said arm and in the general direction of its length toward said guide, said means having associated with it a tension device adapted to exert on said arma gradually increasing operating force as the angle between said arm and .said means increases.

5. In control surface operating mechanism for aircraft, a movable control device, a connection between said control device and the control surface, an arm movable with said control device and with respect thereto from an angular position at one side thereof to a corresponding angular positionat the opposite side thereof, means engaging said arm for holding it in either position of adjustment, and means fastened to said arm for excontrol device and with respect erting thereon and on said control device an 6. In control surface operating mechanism for aircraft, amovable control device, a connection between said control device and the control surface, an arm movable withsaid thereto from an angular positionat one side thereof to a corresponding angular position at the opposite-side thereof,,mea'ns engaging said arm for holding it in either position of adjustment, and means fastened to said arm for exerting thereon and on said control device an force tending to counteract the reoperating sistance ofiered to the angular-movement of saidcontrol surface, and mechanism operable to vary the degree of said operating force.

In testimony whereof we hereunto aflix our signatures,

' -WILLIAM'WAIT, JR.

THEODORE r. WRIGHT; I 

